1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
5 * The Regents of the University of California.
6 * Copyright (c) 2008 Robert N. M. Watson
7 * Copyright (c) 2010-2011 Juniper Networks, Inc.
8 * Copyright (c) 2014 Kevin Lo
9 * All rights reserved.
10 *
11 * Portions of this software were developed by Robert N. M. Watson under
12 * contract to Juniper Networks, Inc.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 * 3. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 */
38
39 #include <sys/cdefs.h>
40 #include "opt_inet.h"
41 #include "opt_inet6.h"
42 #include "opt_ipsec.h"
43 #include "opt_route.h"
44 #include "opt_rss.h"
45
46 #include <sys/param.h>
47 #include <sys/domain.h>
48 #include <sys/eventhandler.h>
49 #include <sys/jail.h>
50 #include <sys/kernel.h>
51 #include <sys/lock.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/priv.h>
55 #include <sys/proc.h>
56 #include <sys/protosw.h>
57 #include <sys/sdt.h>
58 #include <sys/signalvar.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/sx.h>
62 #include <sys/sysctl.h>
63 #include <sys/syslog.h>
64 #include <sys/systm.h>
65
66 #include <vm/uma.h>
67
68 #include <net/if.h>
69 #include <net/if_var.h>
70 #include <net/route.h>
71 #include <net/route/nhop.h>
72 #include <net/rss_config.h>
73
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_fib.h>
77 #include <netinet/in_pcb.h>
78 #include <netinet/in_systm.h>
79 #include <netinet/in_var.h>
80 #include <netinet/ip.h>
81 #ifdef INET6
82 #include <netinet/ip6.h>
83 #endif
84 #include <netinet/ip_icmp.h>
85 #include <netinet/icmp_var.h>
86 #include <netinet/ip_var.h>
87 #include <netinet/ip_options.h>
88 #ifdef INET6
89 #include <netinet6/ip6_var.h>
90 #endif
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93 #include <netinet/udplite.h>
94 #include <netinet/in_rss.h>
95
96 #include <netipsec/ipsec_support.h>
97
98 #include <machine/in_cksum.h>
99
100 #include <security/mac/mac_framework.h>
101
102 /*
103 * UDP and UDP-Lite protocols implementation.
104 * Per RFC 768, August, 1980.
105 * Per RFC 3828, July, 2004.
106 */
107
108 VNET_DEFINE(int, udp_bind_all_fibs) = 1;
109 SYSCTL_INT(_net_inet_udp, OID_AUTO, bind_all_fibs, CTLFLAG_VNET | CTLFLAG_RDTUN,
110 &VNET_NAME(udp_bind_all_fibs), 0,
111 "Bound sockets receive traffic from all FIBs");
112
113 /*
114 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums
115 * removes the only data integrity mechanism for packets and malformed
116 * packets that would otherwise be discarded due to bad checksums, and may
117 * cause problems (especially for NFS data blocks).
118 */
119 VNET_DEFINE(int, udp_cksum) = 1;
120 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
121 &VNET_NAME(udp_cksum), 0, "compute udp checksum");
122
123 VNET_DEFINE(int, udp_log_in_vain) = 0;
124 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
125 &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
126
127 VNET_DEFINE(int, udp_blackhole) = 0;
128 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
129 &VNET_NAME(udp_blackhole), 0,
130 "Do not send port unreachables for refused connects");
131 VNET_DEFINE(bool, udp_blackhole_local) = false;
132 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
133 CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
134 "Enforce net.inet.udp.blackhole for locally originated packets");
135
136 u_long udp_sendspace = 9216; /* really max datagram size */
137 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
138 &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
139
140 u_long udp_recvspace = 40 * (1024 +
141 #ifdef INET6
142 sizeof(struct sockaddr_in6)
143 #else
144 sizeof(struct sockaddr_in)
145 #endif
146 ); /* 40 1K datagrams */
147
148 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
149 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
150
151 VNET_DEFINE(struct inpcbinfo, udbinfo);
152 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
153
154 #ifndef UDBHASHSIZE
155 #define UDBHASHSIZE 128
156 #endif
157
158 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */
159 VNET_PCPUSTAT_SYSINIT(udpstat);
160 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
161 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
162
163 #ifdef VIMAGE
164 VNET_PCPUSTAT_SYSUNINIT(udpstat);
165 #endif /* VIMAGE */
166 #ifdef INET
167 static void udp_detach(struct socket *so);
168 #endif
169
170 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
171 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
172 "udplite", "udplitehash");
173
174 static void
udp_vnet_init(void * arg __unused)175 udp_vnet_init(void *arg __unused)
176 {
177
178 /*
179 * For now default to 2-tuple UDP hashing - until the fragment
180 * reassembly code can also update the flowid.
181 *
182 * Once we can calculate the flowid that way and re-establish
183 * a 4-tuple, flip this to 4-tuple.
184 */
185 in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
186 /* Additional pcbinfo for UDP-Lite */
187 in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
188 UDBHASHSIZE);
189 }
190 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
191 udp_vnet_init, NULL);
192
193 /*
194 * Kernel module interface for updating udpstat. The argument is an index
195 * into udpstat treated as an array of u_long. While this encodes the
196 * general layout of udpstat into the caller, it doesn't encode its location,
197 * so that future changes to add, for example, per-CPU stats support won't
198 * cause binary compatibility problems for kernel modules.
199 */
200 void
kmod_udpstat_inc(int statnum)201 kmod_udpstat_inc(int statnum)
202 {
203
204 counter_u64_add(VNET(udpstat)[statnum], 1);
205 }
206
207 #ifdef VIMAGE
208 static void
udp_destroy(void * unused __unused)209 udp_destroy(void *unused __unused)
210 {
211
212 in_pcbinfo_destroy(&V_udbinfo);
213 in_pcbinfo_destroy(&V_ulitecbinfo);
214 }
215 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
216 #endif
217
218 #ifdef INET
219 /*
220 * Subroutine of udp_input(), which appends the provided mbuf chain to the
221 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that
222 * contains the source address. If the socket ends up being an IPv6 socket,
223 * udp_append() will convert to a sockaddr_in6 before passing the address
224 * into the socket code.
225 *
226 * In the normal case udp_append() will return 'false', indicating that you
227 * must unlock the inpcb. However if a tunneling protocol is in place we
228 * increment the inpcb refcnt and unlock the inpcb, on return from the tunneling
229 * protocol we then decrement the reference count. If in_pcbrele_rlocked()
230 * returns 'true', indicating the inpcb is gone, we return that to the caller
231 * to tell them *not* to unlock the inpcb. In the case of multicast this will
232 * cause the distribution to stop (though most tunneling protocols known
233 * currently do *not* use multicast).
234 *
235 * The mbuf is always consumed.
236 */
237 static bool
udp_append(struct inpcb * inp,struct ip * ip,struct mbuf * n,int off,struct sockaddr_in * udp_in)238 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
239 struct sockaddr_in *udp_in)
240 {
241 struct sockaddr *append_sa;
242 struct socket *so;
243 struct mbuf *tmpopts, *opts = NULL;
244 #ifdef INET6
245 struct sockaddr_in6 udp_in6;
246 #endif
247 struct udpcb *up;
248
249 INP_LOCK_ASSERT(inp);
250
251 /*
252 * Engage the tunneling protocol.
253 */
254 up = intoudpcb(inp);
255 if (up->u_tun_func != NULL) {
256 bool filtered;
257
258 in_pcbref(inp);
259 INP_RUNLOCK(inp);
260 filtered = (*up->u_tun_func)(n, off, inp,
261 (struct sockaddr *)&udp_in[0], up->u_tun_ctx);
262 INP_RLOCK(inp);
263 if (in_pcbrele_rlocked(inp)) {
264 if (!filtered)
265 m_freem(n);
266 return (true);
267 }
268 if (filtered)
269 return (false);
270 }
271
272 off += sizeof(struct udphdr);
273
274 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
275 /* Check AH/ESP integrity. */
276 if (IPSEC_ENABLED(ipv4) &&
277 IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
278 m_freem(n);
279 return (false);
280 }
281 if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
282 if (IPSEC_ENABLED(ipv4) &&
283 UDPENCAP_INPUT(ipv4, n, off, AF_INET) != 0)
284 return (false);
285 }
286 #endif /* IPSEC */
287 #ifdef MAC
288 if (mac_inpcb_check_deliver(inp, n) != 0) {
289 m_freem(n);
290 return (false);
291 }
292 #endif /* MAC */
293 if (inp->inp_flags & INP_CONTROLOPTS ||
294 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
295 #ifdef INET6
296 if (inp->inp_vflag & INP_IPV6)
297 (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
298 else
299 #endif /* INET6 */
300 ip_savecontrol(inp, &opts, ip, n);
301 }
302 if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
303 tmpopts = sbcreatecontrol(&udp_in[1],
304 sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
305 M_NOWAIT);
306 if (tmpopts) {
307 if (opts) {
308 tmpopts->m_next = opts;
309 opts = tmpopts;
310 } else
311 opts = tmpopts;
312 }
313 }
314 #ifdef INET6
315 if (inp->inp_vflag & INP_IPV6) {
316 bzero(&udp_in6, sizeof(udp_in6));
317 udp_in6.sin6_len = sizeof(udp_in6);
318 udp_in6.sin6_family = AF_INET6;
319 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
320 append_sa = (struct sockaddr *)&udp_in6;
321 } else
322 #endif /* INET6 */
323 append_sa = (struct sockaddr *)&udp_in[0];
324 m_adj(n, off);
325
326 so = inp->inp_socket;
327 SOCKBUF_LOCK(&so->so_rcv);
328 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
329 soroverflow_locked(so);
330 m_freem(n);
331 if (opts)
332 m_freem(opts);
333 UDPSTAT_INC(udps_fullsock);
334 } else
335 sorwakeup_locked(so);
336 return (false);
337 }
338
339 static bool
udp_multi_match(const struct inpcb * inp,void * v)340 udp_multi_match(const struct inpcb *inp, void *v)
341 {
342 struct ip *ip = v;
343 struct udphdr *uh = (struct udphdr *)(ip + 1);
344
345 if (inp->inp_lport != uh->uh_dport)
346 return (false);
347 #ifdef INET6
348 if ((inp->inp_vflag & INP_IPV4) == 0)
349 return (false);
350 #endif
351 if (inp->inp_laddr.s_addr != INADDR_ANY &&
352 inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
353 return (false);
354 if (inp->inp_faddr.s_addr != INADDR_ANY &&
355 inp->inp_faddr.s_addr != ip->ip_src.s_addr)
356 return (false);
357 if (inp->inp_fport != 0 &&
358 inp->inp_fport != uh->uh_sport)
359 return (false);
360
361 return (true);
362 }
363
364 static int
udp_multi_input(struct mbuf * m,int proto,struct sockaddr_in * udp_in)365 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
366 {
367 struct ip *ip = mtod(m, struct ip *);
368 struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
369 INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
370 #ifdef KDTRACE_HOOKS
371 struct udphdr *uh = (struct udphdr *)(ip + 1);
372 #endif
373 struct inpcb *inp;
374 struct mbuf *n;
375 int appends = 0, fib;
376
377 MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
378
379 fib = M_GETFIB(m);
380
381 while ((inp = inp_next(&inpi)) != NULL) {
382 /*
383 * XXXRW: Because we weren't holding either the inpcb
384 * or the hash lock when we checked for a match
385 * before, we should probably recheck now that the
386 * inpcb lock is held.
387 */
388
389 if (V_udp_bind_all_fibs == 0 && fib != inp->inp_inc.inc_fibnum)
390 /*
391 * Sockets bound to a specific FIB can only receive
392 * packets from that FIB.
393 */
394 continue;
395
396 /*
397 * Handle socket delivery policy for any-source
398 * and source-specific multicast. [RFC3678]
399 */
400 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
401 struct ip_moptions *imo;
402 struct sockaddr_in group;
403 int blocked;
404
405 imo = inp->inp_moptions;
406 if (imo == NULL)
407 continue;
408 bzero(&group, sizeof(struct sockaddr_in));
409 group.sin_len = sizeof(struct sockaddr_in);
410 group.sin_family = AF_INET;
411 group.sin_addr = ip->ip_dst;
412
413 blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
414 (struct sockaddr *)&group,
415 (struct sockaddr *)&udp_in[0]);
416 if (blocked != MCAST_PASS) {
417 if (blocked == MCAST_NOTGMEMBER)
418 IPSTAT_INC(ips_notmember);
419 if (blocked == MCAST_NOTSMEMBER ||
420 blocked == MCAST_MUTED)
421 UDPSTAT_INC(udps_filtermcast);
422 continue;
423 }
424 }
425 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
426 if (proto == IPPROTO_UDPLITE)
427 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
428 else
429 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
430 if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
431 break;
432 } else
433 appends++;
434 }
435 /*
436 * Don't look for additional matches if this one does
437 * not have either the SO_REUSEPORT or SO_REUSEADDR
438 * socket options set. This heuristic avoids
439 * searching through all pcbs in the common case of a
440 * non-shared port. It assumes that an application
441 * will never clear these options after setting them.
442 */
443 if ((inp->inp_socket->so_options &
444 (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
445 INP_RUNLOCK(inp);
446 break;
447 }
448 }
449
450 if (appends == 0) {
451 /*
452 * No matching pcb found; discard datagram. (No need
453 * to send an ICMP Port Unreachable for a broadcast
454 * or multicast datagram.)
455 */
456 UDPSTAT_INC(udps_noport);
457 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
458 UDPSTAT_INC(udps_noportmcast);
459 else
460 UDPSTAT_INC(udps_noportbcast);
461 }
462 m_freem(m);
463
464 return (IPPROTO_DONE);
465 }
466
467 static int
udp_input(struct mbuf ** mp,int * offp,int proto)468 udp_input(struct mbuf **mp, int *offp, int proto)
469 {
470 struct ip *ip;
471 struct udphdr *uh;
472 struct ifnet *ifp;
473 struct inpcb *inp;
474 uint16_t len, ip_len;
475 struct inpcbinfo *pcbinfo;
476 struct sockaddr_in udp_in[2];
477 struct mbuf *m;
478 struct m_tag *fwd_tag;
479 int cscov_partial, iphlen, lookupflags;
480
481 m = *mp;
482 iphlen = *offp;
483 ifp = m->m_pkthdr.rcvif;
484 *mp = NULL;
485 UDPSTAT_INC(udps_ipackets);
486
487 /*
488 * Strip IP options, if any; should skip this, make available to
489 * user, and use on returned packets, but we don't yet have a way to
490 * check the checksum with options still present.
491 */
492 if (iphlen > sizeof (struct ip)) {
493 ip_stripoptions(m);
494 iphlen = sizeof(struct ip);
495 }
496
497 /*
498 * Get IP and UDP header together in first mbuf.
499 */
500 if (m->m_len < iphlen + sizeof(struct udphdr)) {
501 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
502 UDPSTAT_INC(udps_hdrops);
503 return (IPPROTO_DONE);
504 }
505 }
506 ip = mtod(m, struct ip *);
507 uh = (struct udphdr *)((caddr_t)ip + iphlen);
508 cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
509
510 /*
511 * Destination port of 0 is illegal, based on RFC768.
512 */
513 if (uh->uh_dport == 0)
514 goto badunlocked;
515
516 /*
517 * Construct sockaddr format source address. Stuff source address
518 * and datagram in user buffer.
519 */
520 bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
521 udp_in[0].sin_len = sizeof(struct sockaddr_in);
522 udp_in[0].sin_family = AF_INET;
523 udp_in[0].sin_port = uh->uh_sport;
524 udp_in[0].sin_addr = ip->ip_src;
525 udp_in[1].sin_len = sizeof(struct sockaddr_in);
526 udp_in[1].sin_family = AF_INET;
527 udp_in[1].sin_port = uh->uh_dport;
528 udp_in[1].sin_addr = ip->ip_dst;
529
530 /*
531 * Make mbuf data length reflect UDP length. If not enough data to
532 * reflect UDP length, drop.
533 */
534 len = ntohs((u_short)uh->uh_ulen);
535 ip_len = ntohs(ip->ip_len) - iphlen;
536 if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
537 /* Zero means checksum over the complete packet. */
538 if (len == 0)
539 len = ip_len;
540 cscov_partial = 0;
541 }
542 if (ip_len != len) {
543 if (len > ip_len || len < sizeof(struct udphdr)) {
544 UDPSTAT_INC(udps_badlen);
545 goto badunlocked;
546 }
547 if (proto == IPPROTO_UDP)
548 m_adj(m, len - ip_len);
549 }
550
551 /*
552 * Checksum extended UDP header and data.
553 */
554 if (uh->uh_sum) {
555 u_short uh_sum;
556
557 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
558 !cscov_partial) {
559 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
560 uh_sum = m->m_pkthdr.csum_data;
561 else
562 uh_sum = in_pseudo(ip->ip_src.s_addr,
563 ip->ip_dst.s_addr, htonl((u_short)len +
564 m->m_pkthdr.csum_data + proto));
565 uh_sum ^= 0xffff;
566 } else if (m->m_pkthdr.csum_flags & CSUM_IP_UDP) {
567 /*
568 * Packet from local host (maybe from a VM).
569 * Checksum not required.
570 */
571 uh_sum = 0;
572 } else {
573 char b[offsetof(struct ipovly, ih_src)];
574 struct ipovly *ipov = (struct ipovly *)ip;
575
576 memcpy(b, ipov, sizeof(b));
577 bzero(ipov, sizeof(ipov->ih_x1));
578 ipov->ih_len = (proto == IPPROTO_UDP) ?
579 uh->uh_ulen : htons(ip_len);
580 uh_sum = in_cksum(m, len + sizeof (struct ip));
581 memcpy(ipov, b, sizeof(b));
582 }
583 if (uh_sum) {
584 UDPSTAT_INC(udps_badsum);
585 m_freem(m);
586 return (IPPROTO_DONE);
587 }
588 } else {
589 if (proto == IPPROTO_UDP) {
590 UDPSTAT_INC(udps_nosum);
591 } else {
592 /* UDPLite requires a checksum */
593 /* XXX: What is the right UDPLite MIB counter here? */
594 m_freem(m);
595 return (IPPROTO_DONE);
596 }
597 }
598
599 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
600 in_ifnet_broadcast(ip->ip_dst, ifp))
601 return (udp_multi_input(m, proto, udp_in));
602
603 pcbinfo = udp_get_inpcbinfo(proto);
604
605 /*
606 * Locate pcb for datagram.
607 */
608 lookupflags = INPLOOKUP_RLOCKPCB |
609 (V_udp_bind_all_fibs ? 0 : INPLOOKUP_FIB);
610
611 /*
612 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
613 */
614 if ((m->m_flags & M_IP_NEXTHOP) &&
615 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
616 struct sockaddr_in *next_hop;
617
618 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
619
620 /*
621 * Transparently forwarded. Pretend to be the destination.
622 * Already got one like this?
623 */
624 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
625 ip->ip_dst, uh->uh_dport, lookupflags, ifp, m);
626 if (!inp) {
627 /*
628 * It's new. Try to find the ambushing socket.
629 * Because we've rewritten the destination address,
630 * any hardware-generated hash is ignored.
631 */
632 inp = in_pcblookup(pcbinfo, ip->ip_src,
633 uh->uh_sport, next_hop->sin_addr,
634 next_hop->sin_port ? htons(next_hop->sin_port) :
635 uh->uh_dport, INPLOOKUP_WILDCARD | lookupflags,
636 ifp);
637 }
638 /* Remove the tag from the packet. We don't need it anymore. */
639 m_tag_delete(m, fwd_tag);
640 m->m_flags &= ~M_IP_NEXTHOP;
641 } else
642 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
643 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
644 lookupflags, ifp, m);
645 if (inp == NULL) {
646 if (V_udp_log_in_vain) {
647 char src[INET_ADDRSTRLEN];
648 char dst[INET_ADDRSTRLEN];
649
650 log(LOG_INFO,
651 "Connection attempt to UDP %s:%d from %s:%d\n",
652 inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
653 inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
654 }
655 if (proto == IPPROTO_UDPLITE)
656 UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
657 else
658 UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
659 UDPSTAT_INC(udps_noport);
660 if (m->m_flags & M_MCAST) {
661 UDPSTAT_INC(udps_noportmcast);
662 goto badunlocked;
663 }
664 if (m->m_flags & M_BCAST) {
665 UDPSTAT_INC(udps_noportbcast);
666 goto badunlocked;
667 }
668 if (V_udp_blackhole && (V_udp_blackhole_local ||
669 !in_localip(ip->ip_src)))
670 goto badunlocked;
671 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
672 goto badunlocked;
673 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
674 return (IPPROTO_DONE);
675 }
676
677 /*
678 * Check the minimum TTL for socket.
679 */
680 INP_RLOCK_ASSERT(inp);
681 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
682 if (proto == IPPROTO_UDPLITE)
683 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
684 else
685 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
686 INP_RUNLOCK(inp);
687 m_freem(m);
688 return (IPPROTO_DONE);
689 }
690 if (cscov_partial) {
691 struct udpcb *up;
692
693 up = intoudpcb(inp);
694 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
695 INP_RUNLOCK(inp);
696 m_freem(m);
697 return (IPPROTO_DONE);
698 }
699 }
700
701 if (proto == IPPROTO_UDPLITE)
702 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
703 else
704 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
705 if (!udp_append(inp, ip, m, iphlen, udp_in))
706 INP_RUNLOCK(inp);
707 return (IPPROTO_DONE);
708
709 badunlocked:
710 m_freem(m);
711 return (IPPROTO_DONE);
712 }
713 #endif /* INET */
714
715 /*
716 * Notify a udp user of an asynchronous error; just wake up so that they can
717 * collect error status.
718 */
719 struct inpcb *
udp_notify(struct inpcb * inp,int errno)720 udp_notify(struct inpcb *inp, int errno)
721 {
722
723 INP_WLOCK_ASSERT(inp);
724 if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
725 errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
726 NH_FREE(inp->inp_route.ro_nh);
727 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
728 }
729
730 inp->inp_socket->so_error = errno;
731 sorwakeup(inp->inp_socket);
732 sowwakeup(inp->inp_socket);
733 return (inp);
734 }
735
736 #ifdef INET
737 static void
udp_common_ctlinput(struct icmp * icmp,struct inpcbinfo * pcbinfo)738 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
739 {
740 struct ip *ip = &icmp->icmp_ip;
741 struct udphdr *uh;
742 struct inpcb *inp;
743
744 if (icmp_errmap(icmp) == 0)
745 return;
746
747 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
748 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
749 uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
750 if (inp != NULL) {
751 INP_WLOCK_ASSERT(inp);
752 if (inp->inp_socket != NULL)
753 udp_notify(inp, icmp_errmap(icmp));
754 INP_WUNLOCK(inp);
755 } else {
756 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
757 ip->ip_src, uh->uh_sport,
758 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
759 if (inp != NULL) {
760 struct udpcb *up;
761 udp_tun_icmp_t *func;
762
763 up = intoudpcb(inp);
764 func = up->u_icmp_func;
765 INP_RUNLOCK(inp);
766 if (func != NULL)
767 func(icmp);
768 }
769 }
770 }
771
772 static void
udp_ctlinput(struct icmp * icmp)773 udp_ctlinput(struct icmp *icmp)
774 {
775
776 return (udp_common_ctlinput(icmp, &V_udbinfo));
777 }
778
779 static void
udplite_ctlinput(struct icmp * icmp)780 udplite_ctlinput(struct icmp *icmp)
781 {
782
783 return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
784 }
785 #endif /* INET */
786
787 static int
udp_pcblist(SYSCTL_HANDLER_ARGS)788 udp_pcblist(SYSCTL_HANDLER_ARGS)
789 {
790 struct inpcbinfo *pcbinfo = udp_get_inpcbinfo(arg2);
791 struct inpcb_iterator inpi = INP_ALL_ITERATOR(pcbinfo,
792 INPLOOKUP_RLOCKPCB);
793 struct xinpgen xig;
794 struct inpcb *inp;
795 int error;
796
797 if (req->newptr != 0)
798 return (EPERM);
799
800 if (req->oldptr == 0) {
801 int n;
802
803 n = pcbinfo->ipi_count;
804 n += imax(n / 8, 10);
805 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
806 return (0);
807 }
808
809 if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
810 return (error);
811
812 bzero(&xig, sizeof(xig));
813 xig.xig_len = sizeof xig;
814 xig.xig_count = pcbinfo->ipi_count;
815 xig.xig_gen = pcbinfo->ipi_gencnt;
816 xig.xig_sogen = so_gencnt;
817 error = SYSCTL_OUT(req, &xig, sizeof xig);
818 if (error)
819 return (error);
820
821 while ((inp = inp_next(&inpi)) != NULL) {
822 if (inp->inp_gencnt <= xig.xig_gen &&
823 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
824 struct xinpcb xi;
825
826 in_pcbtoxinpcb(inp, &xi);
827 error = SYSCTL_OUT(req, &xi, sizeof xi);
828 if (error) {
829 INP_RUNLOCK(inp);
830 break;
831 }
832 }
833 }
834
835 if (!error) {
836 /*
837 * Give the user an updated idea of our state. If the
838 * generation differs from what we told her before, she knows
839 * that something happened while we were processing this
840 * request, and it might be necessary to retry.
841 */
842 xig.xig_gen = pcbinfo->ipi_gencnt;
843 xig.xig_sogen = so_gencnt;
844 xig.xig_count = pcbinfo->ipi_count;
845 error = SYSCTL_OUT(req, &xig, sizeof xig);
846 }
847
848 return (error);
849 }
850
851 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
852 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, IPPROTO_UDP,
853 udp_pcblist, "S,xinpcb",
854 "List of active UDP sockets");
855
856 #ifdef INET
857 static int
udp_getcred(SYSCTL_HANDLER_ARGS)858 udp_getcred(SYSCTL_HANDLER_ARGS)
859 {
860 struct xucred xuc;
861 struct sockaddr_in addrs[2];
862 struct epoch_tracker et;
863 struct inpcb *inp;
864 int error;
865
866 if (req->newptr == NULL)
867 return (EINVAL);
868 error = priv_check(req->td, PRIV_NETINET_GETCRED);
869 if (error)
870 return (error);
871 error = SYSCTL_IN(req, addrs, sizeof(addrs));
872 if (error)
873 return (error);
874 NET_EPOCH_ENTER(et);
875 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
876 addrs[0].sin_addr, addrs[0].sin_port,
877 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
878 NET_EPOCH_EXIT(et);
879 if (inp != NULL) {
880 INP_RLOCK_ASSERT(inp);
881 if (inp->inp_socket == NULL)
882 error = ENOENT;
883 if (error == 0)
884 error = cr_canseeinpcb(req->td->td_ucred, inp);
885 if (error == 0)
886 cru2x(inp->inp_cred, &xuc);
887 INP_RUNLOCK(inp);
888 } else
889 error = ENOENT;
890 if (error == 0)
891 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
892 return (error);
893 }
894
895 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
896 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
897 0, 0, udp_getcred, "S,xucred",
898 "Get the xucred of a UDP connection");
899 #endif /* INET */
900
901 int
udp_ctloutput(struct socket * so,struct sockopt * sopt)902 udp_ctloutput(struct socket *so, struct sockopt *sopt)
903 {
904 struct inpcb *inp;
905 struct udpcb *up;
906 int isudplite, error, optval;
907
908 error = 0;
909 isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
910 inp = sotoinpcb(so);
911 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
912 INP_WLOCK(inp);
913 if (sopt->sopt_level != so->so_proto->pr_protocol) {
914 #ifdef INET6
915 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
916 INP_WUNLOCK(inp);
917 error = ip6_ctloutput(so, sopt);
918 }
919 #endif
920 #if defined(INET) && defined(INET6)
921 else
922 #endif
923 #ifdef INET
924 {
925 INP_WUNLOCK(inp);
926 error = ip_ctloutput(so, sopt);
927 }
928 #endif
929 return (error);
930 }
931
932 switch (sopt->sopt_dir) {
933 case SOPT_SET:
934 switch (sopt->sopt_name) {
935 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
936 #if defined(INET) || defined(INET6)
937 case UDP_ENCAP:
938 #ifdef INET
939 if (INP_SOCKAF(so) == AF_INET) {
940 if (!IPSEC_ENABLED(ipv4)) {
941 INP_WUNLOCK(inp);
942 return (ENOPROTOOPT);
943 }
944 error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
945 break;
946 }
947 #endif /* INET */
948 #ifdef INET6
949 if (INP_SOCKAF(so) == AF_INET6) {
950 if (!IPSEC_ENABLED(ipv6)) {
951 INP_WUNLOCK(inp);
952 return (ENOPROTOOPT);
953 }
954 error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
955 break;
956 }
957 #endif /* INET6 */
958 INP_WUNLOCK(inp);
959 return (EINVAL);
960 #endif /* INET || INET6 */
961
962 #endif /* IPSEC */
963 case UDPLITE_SEND_CSCOV:
964 case UDPLITE_RECV_CSCOV:
965 if (!isudplite) {
966 INP_WUNLOCK(inp);
967 error = ENOPROTOOPT;
968 break;
969 }
970 INP_WUNLOCK(inp);
971 error = sooptcopyin(sopt, &optval, sizeof(optval),
972 sizeof(optval));
973 if (error != 0)
974 break;
975 inp = sotoinpcb(so);
976 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
977 INP_WLOCK(inp);
978 up = intoudpcb(inp);
979 KASSERT(up != NULL, ("%s: up == NULL", __func__));
980 if ((optval != 0 && optval < 8) || (optval > 65535)) {
981 INP_WUNLOCK(inp);
982 error = EINVAL;
983 break;
984 }
985 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
986 up->u_txcslen = optval;
987 else
988 up->u_rxcslen = optval;
989 INP_WUNLOCK(inp);
990 break;
991 default:
992 INP_WUNLOCK(inp);
993 error = ENOPROTOOPT;
994 break;
995 }
996 break;
997 case SOPT_GET:
998 switch (sopt->sopt_name) {
999 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1000 #if defined(INET) || defined(INET6)
1001 case UDP_ENCAP:
1002 #ifdef INET
1003 if (INP_SOCKAF(so) == AF_INET) {
1004 if (!IPSEC_ENABLED(ipv4)) {
1005 INP_WUNLOCK(inp);
1006 return (ENOPROTOOPT);
1007 }
1008 error = UDPENCAP_PCBCTL(ipv4, inp, sopt);
1009 break;
1010 }
1011 #endif /* INET */
1012 #ifdef INET6
1013 if (INP_SOCKAF(so) == AF_INET6) {
1014 if (!IPSEC_ENABLED(ipv6)) {
1015 INP_WUNLOCK(inp);
1016 return (ENOPROTOOPT);
1017 }
1018 error = UDPENCAP_PCBCTL(ipv6, inp, sopt);
1019 break;
1020 }
1021 #endif /* INET6 */
1022 INP_WUNLOCK(inp);
1023 return (EINVAL);
1024 #endif /* INET || INET6 */
1025
1026 #endif /* IPSEC */
1027 case UDPLITE_SEND_CSCOV:
1028 case UDPLITE_RECV_CSCOV:
1029 if (!isudplite) {
1030 INP_WUNLOCK(inp);
1031 error = ENOPROTOOPT;
1032 break;
1033 }
1034 up = intoudpcb(inp);
1035 KASSERT(up != NULL, ("%s: up == NULL", __func__));
1036 if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1037 optval = up->u_txcslen;
1038 else
1039 optval = up->u_rxcslen;
1040 INP_WUNLOCK(inp);
1041 error = sooptcopyout(sopt, &optval, sizeof(optval));
1042 break;
1043 default:
1044 INP_WUNLOCK(inp);
1045 error = ENOPROTOOPT;
1046 break;
1047 }
1048 break;
1049 }
1050 return (error);
1051 }
1052
1053 #ifdef INET
1054 #ifdef INET6
1055 /* The logic here is derived from ip6_setpktopt(). See comments there. */
1056 static int
udp_v4mapped_pktinfo(struct cmsghdr * cm,struct sockaddr_in * src,struct inpcb * inp,int flags)1057 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
1058 struct inpcb *inp, int flags)
1059 {
1060 struct ifnet *ifp;
1061 struct in6_pktinfo *pktinfo;
1062 struct in_addr ia;
1063
1064 NET_EPOCH_ASSERT();
1065
1066 if ((flags & PRUS_IPV6) == 0)
1067 return (0);
1068
1069 if (cm->cmsg_level != IPPROTO_IPV6)
1070 return (0);
1071
1072 if (cm->cmsg_type != IPV6_2292PKTINFO &&
1073 cm->cmsg_type != IPV6_PKTINFO)
1074 return (0);
1075
1076 if (cm->cmsg_len !=
1077 CMSG_LEN(sizeof(struct in6_pktinfo)))
1078 return (EINVAL);
1079
1080 pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1081 if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1082 !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1083 return (EINVAL);
1084
1085 /* Validate the interface index if specified. */
1086 if (pktinfo->ipi6_ifindex) {
1087 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1088 if (ifp == NULL)
1089 return (ENXIO);
1090 } else
1091 ifp = NULL;
1092 if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1093 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1094 if (!in_ifhasaddr(ifp, ia))
1095 return (EADDRNOTAVAIL);
1096 }
1097
1098 bzero(src, sizeof(*src));
1099 src->sin_family = AF_INET;
1100 src->sin_len = sizeof(*src);
1101 src->sin_port = inp->inp_lport;
1102 src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1103
1104 return (0);
1105 }
1106 #endif /* INET6 */
1107
1108 int
udp_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * addr,struct mbuf * control,struct thread * td)1109 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1110 struct mbuf *control, struct thread *td)
1111 {
1112 struct inpcb *inp;
1113 struct udpiphdr *ui;
1114 int len, error = 0;
1115 struct in_addr faddr, laddr;
1116 struct cmsghdr *cm;
1117 struct inpcbinfo *pcbinfo;
1118 struct sockaddr_in *sin, src;
1119 struct epoch_tracker et;
1120 int cscov_partial = 0;
1121 int ipflags = 0;
1122 u_short fport, lport;
1123 u_char tos, vflagsav;
1124 uint8_t pr;
1125 uint16_t cscov = 0;
1126 uint32_t flowid = 0;
1127 uint8_t flowtype = M_HASHTYPE_NONE;
1128 bool use_cached_route;
1129
1130 inp = sotoinpcb(so);
1131 KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1132
1133 if (addr != NULL) {
1134 if (addr->sa_family != AF_INET)
1135 error = EAFNOSUPPORT;
1136 else if (addr->sa_len != sizeof(struct sockaddr_in))
1137 error = EINVAL;
1138 if (__predict_false(error != 0)) {
1139 m_freem(control);
1140 m_freem(m);
1141 return (error);
1142 }
1143 }
1144
1145 len = m->m_pkthdr.len;
1146 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1147 if (control)
1148 m_freem(control);
1149 m_freem(m);
1150 return (EMSGSIZE);
1151 }
1152
1153 src.sin_family = 0;
1154 sin = (struct sockaddr_in *)addr;
1155
1156 /*
1157 * udp_send() may need to bind the current inpcb. As such, we don't
1158 * know up front whether we will need the pcbinfo lock or not. Do any
1159 * work to decide what is needed up front before acquiring any locks.
1160 *
1161 * We will need network epoch in either case, to safely lookup into
1162 * pcb hash.
1163 */
1164 use_cached_route = sin == NULL || (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0);
1165 if (use_cached_route || (flags & PRUS_IPV6) != 0)
1166 INP_WLOCK(inp);
1167 else
1168 INP_RLOCK(inp);
1169 NET_EPOCH_ENTER(et);
1170 tos = inp->inp_ip_tos;
1171 if (control != NULL) {
1172 /*
1173 * XXX: Currently, we assume all the optional information is
1174 * stored in a single mbuf.
1175 */
1176 if (control->m_next) {
1177 m_freem(control);
1178 error = EINVAL;
1179 goto release;
1180 }
1181 for (; control->m_len > 0;
1182 control->m_data += CMSG_ALIGN(cm->cmsg_len),
1183 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1184 cm = mtod(control, struct cmsghdr *);
1185 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1186 || cm->cmsg_len > control->m_len) {
1187 error = EINVAL;
1188 break;
1189 }
1190 #ifdef INET6
1191 error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1192 if (error != 0)
1193 break;
1194 #endif
1195 if (cm->cmsg_level != IPPROTO_IP)
1196 continue;
1197
1198 switch (cm->cmsg_type) {
1199 case IP_SENDSRCADDR:
1200 if (cm->cmsg_len !=
1201 CMSG_LEN(sizeof(struct in_addr))) {
1202 error = EINVAL;
1203 break;
1204 }
1205 bzero(&src, sizeof(src));
1206 src.sin_family = AF_INET;
1207 src.sin_len = sizeof(src);
1208 src.sin_port = inp->inp_lport;
1209 src.sin_addr =
1210 *(struct in_addr *)CMSG_DATA(cm);
1211 break;
1212
1213 case IP_TOS:
1214 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1215 error = EINVAL;
1216 break;
1217 }
1218 tos = *(u_char *)CMSG_DATA(cm);
1219 break;
1220
1221 case IP_FLOWID:
1222 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1223 error = EINVAL;
1224 break;
1225 }
1226 flowid = *(uint32_t *) CMSG_DATA(cm);
1227 break;
1228
1229 case IP_FLOWTYPE:
1230 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1231 error = EINVAL;
1232 break;
1233 }
1234 flowtype = *(uint32_t *) CMSG_DATA(cm);
1235 break;
1236
1237 #ifdef RSS
1238 case IP_RSSBUCKETID:
1239 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1240 error = EINVAL;
1241 break;
1242 }
1243 /* This is just a placeholder for now */
1244 break;
1245 #endif /* RSS */
1246 default:
1247 error = ENOPROTOOPT;
1248 break;
1249 }
1250 if (error)
1251 break;
1252 }
1253 m_freem(control);
1254 control = NULL;
1255 }
1256 if (error)
1257 goto release;
1258
1259 pr = inp->inp_socket->so_proto->pr_protocol;
1260 pcbinfo = udp_get_inpcbinfo(pr);
1261
1262 /*
1263 * If the IP_SENDSRCADDR control message was specified, override the
1264 * source address for this datagram. Its use is invalidated if the
1265 * address thus specified is incomplete or clobbers other inpcbs.
1266 */
1267 laddr = inp->inp_laddr;
1268 lport = inp->inp_lport;
1269 if (src.sin_family == AF_INET) {
1270 if ((lport == 0) ||
1271 (laddr.s_addr == INADDR_ANY &&
1272 src.sin_addr.s_addr == INADDR_ANY)) {
1273 error = EINVAL;
1274 goto release;
1275 }
1276 if ((flags & PRUS_IPV6) != 0) {
1277 vflagsav = inp->inp_vflag;
1278 inp->inp_vflag |= INP_IPV4;
1279 inp->inp_vflag &= ~INP_IPV6;
1280 }
1281 INP_HASH_WLOCK(pcbinfo);
1282 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1283 V_udp_bind_all_fibs ? 0 : INPBIND_FIB, td->td_ucred);
1284 INP_HASH_WUNLOCK(pcbinfo);
1285 if ((flags & PRUS_IPV6) != 0)
1286 inp->inp_vflag = vflagsav;
1287 if (error)
1288 goto release;
1289 }
1290
1291 /*
1292 * If a UDP socket has been connected, then a local address/port will
1293 * have been selected and bound.
1294 *
1295 * If a UDP socket has not been connected to, then an explicit
1296 * destination address must be used, in which case a local
1297 * address/port may not have been selected and bound.
1298 */
1299 if (sin != NULL) {
1300 INP_LOCK_ASSERT(inp);
1301 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1302 error = EISCONN;
1303 goto release;
1304 }
1305
1306 /*
1307 * Jail may rewrite the destination address, so let it do
1308 * that before we use it.
1309 */
1310 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1311 if (error)
1312 goto release;
1313 /*
1314 * sendto(2) on unconnected UDP socket results in implicit
1315 * binding to INADDR_ANY and anonymous port. This has two
1316 * side effects:
1317 * 1) after first sendto(2) the socket will receive datagrams
1318 * destined to the selected port.
1319 * 2) subsequent sendto(2) calls will use the same source port.
1320 */
1321 if (inp->inp_lport == 0) {
1322 struct sockaddr_in wild = {
1323 .sin_family = AF_INET,
1324 .sin_len = sizeof(struct sockaddr_in),
1325 };
1326
1327 INP_HASH_WLOCK(pcbinfo);
1328 error = in_pcbbind(inp, &wild, V_udp_bind_all_fibs ?
1329 0 : INPBIND_FIB, td->td_ucred);
1330 INP_HASH_WUNLOCK(pcbinfo);
1331 if (error)
1332 goto release;
1333 lport = inp->inp_lport;
1334 laddr = inp->inp_laddr;
1335 }
1336 if (laddr.s_addr == INADDR_ANY) {
1337 error = in_pcbladdr(inp, &sin->sin_addr, &laddr,
1338 td->td_ucred);
1339 if (error)
1340 goto release;
1341 }
1342 faddr = sin->sin_addr;
1343 fport = sin->sin_port;
1344 } else {
1345 INP_LOCK_ASSERT(inp);
1346 faddr = inp->inp_faddr;
1347 fport = inp->inp_fport;
1348 if (faddr.s_addr == INADDR_ANY) {
1349 error = ENOTCONN;
1350 goto release;
1351 }
1352 }
1353
1354 /*
1355 * Calculate data length and get a mbuf for UDP, IP, and possible
1356 * link-layer headers. Immediate slide the data pointer back forward
1357 * since we won't use that space at this layer.
1358 */
1359 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1360 if (m == NULL) {
1361 error = ENOBUFS;
1362 goto release;
1363 }
1364 m->m_data += max_linkhdr;
1365 m->m_len -= max_linkhdr;
1366 m->m_pkthdr.len -= max_linkhdr;
1367
1368 /*
1369 * Fill in mbuf with extended UDP header and addresses and length put
1370 * into network format.
1371 */
1372 ui = mtod(m, struct udpiphdr *);
1373 /*
1374 * Filling only those fields of udpiphdr that participate in the
1375 * checksum calculation. The rest must be zeroed and will be filled
1376 * later.
1377 */
1378 bzero(ui->ui_x1, sizeof(ui->ui_x1));
1379 ui->ui_pr = pr;
1380 ui->ui_src = laddr;
1381 ui->ui_dst = faddr;
1382 ui->ui_sport = lport;
1383 ui->ui_dport = fport;
1384 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1385 if (pr == IPPROTO_UDPLITE) {
1386 struct udpcb *up;
1387 uint16_t plen;
1388
1389 up = intoudpcb(inp);
1390 cscov = up->u_txcslen;
1391 plen = (u_short)len + sizeof(struct udphdr);
1392 if (cscov >= plen)
1393 cscov = 0;
1394 ui->ui_len = htons(plen);
1395 ui->ui_ulen = htons(cscov);
1396 /*
1397 * For UDP-Lite, checksum coverage length of zero means
1398 * the entire UDPLite packet is covered by the checksum.
1399 */
1400 cscov_partial = (cscov == 0) ? 0 : 1;
1401 }
1402
1403 if (inp->inp_socket->so_options & SO_DONTROUTE)
1404 ipflags |= IP_ROUTETOIF;
1405 if (inp->inp_socket->so_options & SO_BROADCAST)
1406 ipflags |= IP_ALLOWBROADCAST;
1407 if (inp->inp_flags & INP_ONESBCAST)
1408 ipflags |= IP_SENDONES;
1409
1410 #ifdef MAC
1411 mac_inpcb_create_mbuf(inp, m);
1412 #endif
1413
1414 /*
1415 * Set up checksum and output datagram.
1416 */
1417 ui->ui_sum = 0;
1418 if (pr == IPPROTO_UDPLITE) {
1419 if (inp->inp_flags & INP_ONESBCAST)
1420 faddr.s_addr = INADDR_BROADCAST;
1421 if (cscov_partial) {
1422 if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1423 ui->ui_sum = 0xffff;
1424 } else {
1425 if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1426 ui->ui_sum = 0xffff;
1427 }
1428 } else if (V_udp_cksum) {
1429 if (inp->inp_flags & INP_ONESBCAST)
1430 faddr.s_addr = INADDR_BROADCAST;
1431 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1432 htons((u_short)len + sizeof(struct udphdr) + pr));
1433 m->m_pkthdr.csum_flags = CSUM_UDP;
1434 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1435 }
1436 /*
1437 * After finishing the checksum computation, fill the remaining fields
1438 * of udpiphdr.
1439 */
1440 ((struct ip *)ui)->ip_v = IPVERSION;
1441 ((struct ip *)ui)->ip_tos = tos;
1442 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1443 if (inp->inp_flags & INP_DONTFRAG)
1444 ((struct ip *)ui)->ip_off |= htons(IP_DF);
1445 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;
1446 UDPSTAT_INC(udps_opackets);
1447
1448 /*
1449 * Setup flowid / RSS information for outbound socket.
1450 *
1451 * Once the UDP code decides to set a flowid some other way,
1452 * this allows the flowid to be overridden by userland.
1453 */
1454 if (flowtype != M_HASHTYPE_NONE) {
1455 m->m_pkthdr.flowid = flowid;
1456 M_HASHTYPE_SET(m, flowtype);
1457 }
1458 #if defined(ROUTE_MPATH) || defined(RSS)
1459 else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1460 uint32_t hash_val, hash_type;
1461
1462 hash_val = fib4_calc_packet_hash(laddr, faddr,
1463 lport, fport, pr, &hash_type);
1464 m->m_pkthdr.flowid = hash_val;
1465 M_HASHTYPE_SET(m, hash_type);
1466 }
1467
1468 /*
1469 * Don't override with the inp cached flowid value.
1470 *
1471 * Depending upon the kind of send being done, the inp
1472 * flowid/flowtype values may actually not be appropriate
1473 * for this particular socket send.
1474 *
1475 * We should either leave the flowid at zero (which is what is
1476 * currently done) or set it to some software generated
1477 * hash value based on the packet contents.
1478 */
1479 ipflags |= IP_NODEFAULTFLOWID;
1480 #endif /* RSS */
1481
1482 if (pr == IPPROTO_UDPLITE)
1483 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1484 else
1485 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1486 error = ip_output(m, inp->inp_options,
1487 use_cached_route ? &inp->inp_route : NULL, ipflags,
1488 inp->inp_moptions, inp);
1489 INP_UNLOCK(inp);
1490 NET_EPOCH_EXIT(et);
1491 return (error);
1492
1493 release:
1494 INP_UNLOCK(inp);
1495 NET_EPOCH_EXIT(et);
1496 m_freem(m);
1497 return (error);
1498 }
1499
1500 void
udp_abort(struct socket * so)1501 udp_abort(struct socket *so)
1502 {
1503 struct inpcb *inp;
1504 struct inpcbinfo *pcbinfo;
1505
1506 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1507 inp = sotoinpcb(so);
1508 KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1509 INP_WLOCK(inp);
1510 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1511 INP_HASH_WLOCK(pcbinfo);
1512 in_pcbdisconnect(inp);
1513 INP_HASH_WUNLOCK(pcbinfo);
1514 soisdisconnected(so);
1515 }
1516 INP_WUNLOCK(inp);
1517 }
1518
1519 static int
udp_attach(struct socket * so,int proto,struct thread * td)1520 udp_attach(struct socket *so, int proto, struct thread *td)
1521 {
1522 static uint32_t udp_flowid;
1523 struct inpcbinfo *pcbinfo;
1524 struct inpcb *inp;
1525 struct udpcb *up;
1526 int error;
1527
1528 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1529 inp = sotoinpcb(so);
1530 KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1531 error = soreserve(so, udp_sendspace, udp_recvspace);
1532 if (error)
1533 return (error);
1534 error = in_pcballoc(so, pcbinfo);
1535 if (error)
1536 return (error);
1537
1538 inp = sotoinpcb(so);
1539 inp->inp_ip_ttl = V_ip_defttl;
1540 inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1541 inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1542 up = intoudpcb(inp);
1543 bzero(&up->u_start_zero, u_zero_size);
1544 INP_WUNLOCK(inp);
1545
1546 return (0);
1547 }
1548 #endif /* INET */
1549
1550 int
udp_set_kernel_tunneling(struct socket * so,udp_tun_func_t f,udp_tun_icmp_t i,void * ctx)1551 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1552 {
1553 struct inpcb *inp;
1554 struct udpcb *up;
1555
1556 KASSERT(so->so_type == SOCK_DGRAM,
1557 ("udp_set_kernel_tunneling: !dgram"));
1558 inp = sotoinpcb(so);
1559 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1560 INP_WLOCK(inp);
1561 up = intoudpcb(inp);
1562 if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1563 (up->u_icmp_func != NULL))) {
1564 INP_WUNLOCK(inp);
1565 return (EBUSY);
1566 }
1567 up->u_tun_func = f;
1568 up->u_icmp_func = i;
1569 up->u_tun_ctx = ctx;
1570 INP_WUNLOCK(inp);
1571 return (0);
1572 }
1573
1574 #ifdef INET
1575 static int
udp_bind(struct socket * so,struct sockaddr * nam,struct thread * td)1576 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1577 {
1578 struct inpcb *inp;
1579 struct inpcbinfo *pcbinfo;
1580 struct sockaddr_in *sinp;
1581 int error;
1582
1583 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1584 inp = sotoinpcb(so);
1585 KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1586
1587 sinp = (struct sockaddr_in *)nam;
1588 if (nam->sa_family != AF_INET) {
1589 /*
1590 * Preserve compatibility with old programs.
1591 */
1592 if (nam->sa_family != AF_UNSPEC ||
1593 nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1594 sinp->sin_addr.s_addr != INADDR_ANY)
1595 return (EAFNOSUPPORT);
1596 nam->sa_family = AF_INET;
1597 }
1598 if (nam->sa_len != sizeof(struct sockaddr_in))
1599 return (EINVAL);
1600
1601 INP_WLOCK(inp);
1602 INP_HASH_WLOCK(pcbinfo);
1603 error = in_pcbbind(inp, sinp, V_udp_bind_all_fibs ? 0 : INPBIND_FIB,
1604 td->td_ucred);
1605 INP_HASH_WUNLOCK(pcbinfo);
1606 INP_WUNLOCK(inp);
1607 return (error);
1608 }
1609
1610 static void
udp_close(struct socket * so)1611 udp_close(struct socket *so)
1612 {
1613 struct inpcb *inp;
1614 struct inpcbinfo *pcbinfo;
1615
1616 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1617 inp = sotoinpcb(so);
1618 KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1619 INP_WLOCK(inp);
1620 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1621 INP_HASH_WLOCK(pcbinfo);
1622 in_pcbdisconnect(inp);
1623 INP_HASH_WUNLOCK(pcbinfo);
1624 soisdisconnected(so);
1625 }
1626 INP_WUNLOCK(inp);
1627 }
1628
1629 static int
udp_connect(struct socket * so,struct sockaddr * nam,struct thread * td)1630 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1631 {
1632 struct epoch_tracker et;
1633 struct inpcb *inp;
1634 struct inpcbinfo *pcbinfo;
1635 struct sockaddr_in *sin;
1636 int error;
1637
1638 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1639 inp = sotoinpcb(so);
1640 KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1641
1642 sin = (struct sockaddr_in *)nam;
1643 if (sin->sin_family != AF_INET)
1644 return (EAFNOSUPPORT);
1645 if (sin->sin_len != sizeof(*sin))
1646 return (EINVAL);
1647
1648 INP_WLOCK(inp);
1649 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1650 INP_WUNLOCK(inp);
1651 return (EISCONN);
1652 }
1653 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1654 if (error != 0) {
1655 INP_WUNLOCK(inp);
1656 return (error);
1657 }
1658 NET_EPOCH_ENTER(et);
1659 INP_HASH_WLOCK(pcbinfo);
1660 error = in_pcbconnect(inp, sin, td->td_ucred);
1661 INP_HASH_WUNLOCK(pcbinfo);
1662 NET_EPOCH_EXIT(et);
1663 if (error == 0)
1664 soisconnected(so);
1665 INP_WUNLOCK(inp);
1666 return (error);
1667 }
1668
1669 static void
udp_detach(struct socket * so)1670 udp_detach(struct socket *so)
1671 {
1672 struct inpcb *inp;
1673
1674 inp = sotoinpcb(so);
1675 KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1676 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1677 ("udp_detach: not disconnected"));
1678 INP_WLOCK(inp);
1679 in_pcbfree(inp);
1680 }
1681
1682 int
udp_disconnect(struct socket * so)1683 udp_disconnect(struct socket *so)
1684 {
1685 struct inpcb *inp;
1686 struct inpcbinfo *pcbinfo;
1687
1688 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1689 inp = sotoinpcb(so);
1690 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1691 INP_WLOCK(inp);
1692 if (inp->inp_faddr.s_addr == INADDR_ANY) {
1693 INP_WUNLOCK(inp);
1694 return (ENOTCONN);
1695 }
1696 INP_HASH_WLOCK(pcbinfo);
1697 in_pcbdisconnect(inp);
1698 INP_HASH_WUNLOCK(pcbinfo);
1699 SOCK_LOCK(so);
1700 so->so_state &= ~SS_ISCONNECTED; /* XXX */
1701 SOCK_UNLOCK(so);
1702 INP_WUNLOCK(inp);
1703 return (0);
1704 }
1705 #endif /* INET */
1706
1707 int
udp_shutdown(struct socket * so,enum shutdown_how how)1708 udp_shutdown(struct socket *so, enum shutdown_how how)
1709 {
1710 int error;
1711
1712 SOCK_LOCK(so);
1713 if (!(so->so_state & SS_ISCONNECTED))
1714 /*
1715 * POSIX mandates us to just return ENOTCONN when shutdown(2) is
1716 * invoked on a datagram sockets, however historically we would
1717 * actually tear socket down. This is known to be leveraged by
1718 * some applications to unblock process waiting in recv(2) by
1719 * other process that it shares that socket with. Try to meet
1720 * both backward-compatibility and POSIX requirements by forcing
1721 * ENOTCONN but still flushing buffers and performing wakeup(9).
1722 *
1723 * XXXGL: it remains unknown what applications expect this
1724 * behavior and is this isolated to unix/dgram or inet/dgram or
1725 * both. See: D10351, D3039.
1726 */
1727 error = ENOTCONN;
1728 else
1729 error = 0;
1730 SOCK_UNLOCK(so);
1731
1732 switch (how) {
1733 case SHUT_RD:
1734 sorflush(so);
1735 break;
1736 case SHUT_RDWR:
1737 sorflush(so);
1738 /* FALLTHROUGH */
1739 case SHUT_WR:
1740 socantsendmore(so);
1741 }
1742
1743 return (error);
1744 }
1745
1746 #ifdef INET
1747 #define UDP_PROTOSW \
1748 .pr_type = SOCK_DGRAM, \
1749 .pr_flags = PR_ATOMIC | PR_ADDR | PR_CAPATTACH, \
1750 .pr_ctloutput = udp_ctloutput, \
1751 .pr_abort = udp_abort, \
1752 .pr_attach = udp_attach, \
1753 .pr_bind = udp_bind, \
1754 .pr_connect = udp_connect, \
1755 .pr_control = in_control, \
1756 .pr_detach = udp_detach, \
1757 .pr_disconnect = udp_disconnect, \
1758 .pr_peeraddr = in_getpeeraddr, \
1759 .pr_send = udp_send, \
1760 .pr_soreceive = soreceive_dgram, \
1761 .pr_sosend = sosend_dgram, \
1762 .pr_shutdown = udp_shutdown, \
1763 .pr_sockaddr = in_getsockaddr, \
1764 .pr_sosetlabel = in_pcbsosetlabel, \
1765 .pr_close = udp_close
1766
1767 struct protosw udp_protosw = {
1768 .pr_protocol = IPPROTO_UDP,
1769 UDP_PROTOSW
1770 };
1771
1772 struct protosw udplite_protosw = {
1773 .pr_protocol = IPPROTO_UDPLITE,
1774 UDP_PROTOSW
1775 };
1776
1777 static void
udp_init(void * arg __unused)1778 udp_init(void *arg __unused)
1779 {
1780
1781 IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1782 IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1783 }
1784 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1785 #endif /* INET */
1786